plus4emu is a portable emulator of the Commodore Plus/4 computer. It supports Windows and POSIX platforms (32 bit Windows, 32 and 64 bit Linux, and Mac OS X have been tested). It implements accurate, high quality hardware emulation, but the system requirements are higher than that of most other emulators.
pmping is a script that pings multiple hosts in parallel and gives audible results depending on host state. The sounds come from the internal PC speaker, thus not needing a sound card. It beeps when a host OS is losing many packets, or when it is down. If the host is down, the script can send an email notification or run a command. All aspects are fully customisable by the user.
Poezio is a console-based client for XMPP, the protocol on which the Jabber IM network is built. Its goal is to let you connect to the network very easily (without having to create an account) and join various chatrooms immediately. It tries to look like the most famous IRC clients (such as weechat and irssi). Many commands are identical and you won't be lost if you already know these clients. Configuration can be done in a configuration file or directly from the client. It embodies the light, fast, geeky, and anonymous spirit of IRC while using a new, powerful, standard, and open protocol.
Polypy is a small program to analyze rings in structures read from xyz files. This can be used, for example, to identify defects in crystal structures. The program was initially developed to analyze graphitic carbon structures, but can be used for any other structure. It includes: ring search using Franzblau statistics [Phys. Rev. B 44, 4925]; output structures marked by ring size, which can used for visualization in a program such as VMD; and extensive output with which atoms are in which ring and the neighbors of each atom.
pop3ml is a program to manage mailing lists and newsletters without a local SMTP server. It requires only a simple POP3 email account. It's highly configurable by users. You can subscribe or unsubscribe simply with email messages. There is optional subscription and unsubscription confirmation, subscription moderation, message moderation, digest message mode, parent/children list management, mail scheduling to postpone or repeat a message, a mail filter (with a procmail-like syntax), a message queue for unsent messages, message size check, a command to retrieve messages, bounce detection, message header management, black/white/allow/deny lists, and other functions. There is also a program to test list settings without sending any messages and another program to view and search through stored messages. You can configure it with programs like phpMyAdmin.